1. Field of the Invention
The present invention relates to controlling the motion of a robot.
2. Description of Background Art
Safety is a primary concern that should be addressed before humanoid robots can freely exist in human surroundings. Out of a number of possible situations where safety becomes an issue, one that involves a fall is particularly worrisome. A humanoid robot falling from an upright (e.g., standing or walking) posture can cause damage to delicate and expensive objects in the surroundings or injury to a nearby human being.
A humanoid robot fall may be caused due to unexpected or excessive external forces, unusual or unknown slipperiness, or the slope or profile of the ground. The fall may involve the robot slipping, tripping, or toppling. When the disturbances that threaten balance are larger than what the robot's balance controller can handle, the robot falls. Regardless of the substantial progress in humanoid robot balance control strategies, the possibility of a fall, however remote, remains real, even unavoidable. What is needed are techniques for reducing the damage to objects in the surroundings of a humanoid robot when the robot falls.